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The Physics Behind Waterslides
theodp writes "National Geographic takes a high-level look at the physics behind waterslides. A lot of science goes into providing a safe 60 mph trip down slides like Walt Disney World's 10-story Summit Plummet. 'Safety is our number one concern,' explains Rick Hunter of ProSlide Technology. 'We're thinking about things like, "are you going to stay on the fiberglass tube," it's really easy to do a computer model and look at curves and drops and forecast rider position and speed.'"
How many slashdotters have been to a water park recently, and by water park you can include a shower.
I never did get to visit that park as a kid. Weird NJ has a ton of stories on their site about that place. The slides were dangerous simply because they didn't have past data or computer modeling (that the OP talks about) when designing them, so they winged it and called the park's attractions "extreme". Some of the slides survive in Action Park's successor, Mountain Creek. The looping water slide didn't make the cut though.
Personally, I found Blizzard Beach's Slush Gusher (the slide adjacent to Summit Plummet) to be more unsettling during the descent. While Summit Plummet is fast, you don't really get to see much on your way down and it's over in a matter of seconds. The Slush Gusher levels out twice during descent along a straight path. After I'd reached enough speed by the 3rd drop, my body had left the fiberglass tube. I'm sure they're more concerned with exiting either side of the tube while descending, but when you're not expecting it to happen it is the slightest bit disconcerting to feel the slide 'leave', even for a moment.
Prove it.
"We know from Galileo that all objects near the surface of the Earth accelerate downward at the same rate," he says. "But you also have to think about air resistance. That's why a bowling ball and a piece of paper don't fall at the same rate. You accelerate at a certain rate, but the force that's pulling you down depends on that number and your mass."
Everyone knows this. But then...
As for rides with steep drops instead of curves, heavier riders do go faster, he says.
Now I am confused. Is this assuming heavy riders have more friction with the slide/water or more air resistance or that Newtonian Physics can suck a fat one?
Heavy riders experience less relative resistance, since an object (er, a human's) mass increases faster than the area in contact with the slide. Same goes for wind resistance but i suspect it plays a smaller role.
I visited that Park. A lot Grew up about 45 minutes away from there. Had friends who "lifeguarded" there.
A little bit of background for everyone: the park was located in Vernon, New Jersey (USA), built into the side of a small mountain, hence it's successor's name being Mountain Creek. It was a combination water park / Ski resort, depending on the time of the year.
Perhaps one of the best ways to think about this place is to imagine your favourite water park, saying to yourself "Gee, that ride is great, but I wish I could do...blah...which is prohibited by the rules and the lifeguards would throw me out.". Now imagine that same situation, except that there was no getting thrown out and no one cared about the rules. It was the inmates running the asylum a lot of times. Sure, it made it a metric ton of fun, but the injuries were often severe. Broken legs, dislocated everything, electrocutions....the ambulance was in very frequent use in that place. Some of it was the ride design, as the safeguards and engineering just weren't there. The rest....well, for insance, they had a "Cliff Dive". It was just that....a rocky outcropping about 35' above the main pool. They had weight restrictions, height restrictions, warnings about this and that....and it was all roundly ignored. The lifeguards were supposed to keep the landing area clear, but sometimes they screwed up and damn near had one person landing on another. Oh, and they warned you not to straight dive in, as you could theoretically hit the bottom. Theory, my ass. You could do it pretty easily. As I said....the engineering wasn't. They ran that park cheap, charged a decent amount for admission, and smiled all the way to the bank.
But, as bad as it was, there were hundreds of thousands of folks who came though there with little more than a smile and some sunburn. For a grabasstic teenager, it was a Paradise.
Chris Knight is my hero.
Watersides are just slippery slopes.... Which is a logical argument...
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